Chinese patent application No. 200910105878.0 has disclosed a high-power LED lamp structure with a fan, the fan can effectively cool a radiator and a metal substrate to make a LED illuminant maintain low operating temperature, which helps the LED lamp work normally. In addition, an external end of the LED illuminant is provided with an optical component which is used for light diffusion, light reflections and/or light gathering, in this way, the high-power LED lamp can meet the requirements of various occasions. The high-power LED lamp structure with a fan comprises a high-power LED illuminant, a metal substrate for fixing the high-power LED illuminant and a radiator connected to the metal substrate. The metal substrate is arranged in front of the radiator, and the radiator is also provided with a fan; the radiator is a tubular body with a hollow cavity, and the fan is fixed at the center of an end of the radiator. An external ring of the radiator is provided with a plurality of fins, an external end of the LED illuminant is provided with an optical component which is used for the optical treatment of LED light, furthermore, an end of the radiator is circularly provided with a lamp cap having a LED driving circuit therein. However, the fan only cools the fins of the LED lamp, therefore, this kind of LED lamp will have a low heat dissipation efficiency if there is no air flow channel in inner cavity of the LED lamp.
Besides, a low-power LED lamp can maintain a proper temperature due to its cooling fin. However, when larger luminous flux is required, dissipation of heat generated by the LED lamp then becomes a problem.